Q. When we studied high school biology, our teacher said more than 99 percent of animals lay eggs and only a few give live birth. That percentage seems too high. Humans, dogs, cats and cows are ...

Most people assume that only reptiles, fish, and birds lay eggs — after all, that’s what we learned in school. But nature always has a few surprises up its sleeve. Believe it or not, there are ...

The identification of a key gene in monotremes has increased our understanding of why the stomachs of platypuses and echidnas are atypically small, non-acidic, and, in the instance of platypuses, lack ...

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Q. When we studied high school biology, our teacher said more than 99% of animals lay eggs and only a few give live birth. That percentage seems too high. Humans, dogs, cats and cows are ...